The number of research papers published in scientific journals is exponentially increased during the last years. In a recent study by Van Noorden, based on publications in Web of Science, it is demonstrated that the growth rate of publications, was 1% in the 18th century, to 2 to 3% in the period between the two world wars, and 8 to 9% up to 2010. This evolution of scientific output is equivalent to a doubling every nine years. Thus, the writing of a review paper, a research project proposal or the significant part of any research paper regarding the related literature, a researcher is called to analyze a vast amount of research papers. Accordingly, new terminology, as well as techniques, appear, called bibliometric analysis, bibliometrics, scientometrics, scientific mapping etc., where with the aid of computer algorithms, is possible to analyze a vast amount of research papers, substituting the typical reviews made by individual researchers. The main purpose of this numerical elaboration is to construct bibliometric maps of the field studied. Bibliometric maps relate associations of keywords, authors, journals as well as references, though their distances on a two-dimensional map, revealing significant information about how the papers studied are interrelated by their simultaneous appearance in research papers. Thus, the conclusions regarding the scientific field studied, are based on an extended database of papers, and through a rigor computational procedure, the outcome is precisely documented.
Utilization of the bibliometric maps
- In depth analysis of some hundreds, thousands, or even tens of thousands of papers
- Reveal the significant research topics in each subject area
- Identify associations between thematic areas, authors, references, institutions etc.
- Handle the exponential growth rate of scientific output
- Document literature review thoroughly
- Avoid focusing on topics of minor interest
- Detect interdisciplinary associations (i.e. risk assessment in Medicine and Engineering)
Similarities between research objects
- Colored Similarity Matrix of keywords
- Co-occurrences of keywords
- Database regarding studied topic
Bibliometric Maps – Keywords
- Each object is positioned in a (x,y) point
- The objects with co-occurrences are connected though a line.
- The width of the line is proportional to the similarity (co-occurrence) between the objects.
- The distances between the objects are indicators of their dis-similarity.
- Each object font size is proportional to its number of occurrences.
- In the middle of each link presented the dis-similarities (distances)
Bibliometric Maps – Authors
- Bibliometric maps of co-occurrence of authors’ names in a paper
- Research cooperating groups
- Co-authors with greater amount of papers in common, have reduced distance (inversed relationship)
Bibliometric Maps – References
- bibliometric map of the references
- database regarding studied topic
- major and minor clusters of papers
- focus on a specific cluster, by zooming to a specific region of the map